Clamp device for electric welding-machines.



No.. 719,508. PATENTED EEB. 3, 1903.

A. E. RIETZEL.

CLAMP DEVICE FOR ELECTRIC WELDING MACHINES.

APPLICATION FILED JUNE 14, 1902. I0 MODEL. 3 SHEETS-SHEET 1 .Il l' l'III Il' II'III III'IQ@ l ,Il

Norms vrins ed. PHoTo-Lrmof. wnsmuamn n c No. 719,508. PATENTED FEB. 3,1903. Al I. RIETZEL.

CLAMP DEVICE I'CR ELECTRIC WELDING MACHINES. AIPLIGATION FILED JUNHM,1902.

No MGDBL. -3 SHEETS-SHEET 2.

' cmomgg PATENIED PEB. 3, 1903. A. I. RIEIZEL.

CLAMP DEVICE FCR ELECTRIC WELDING MACHINES.

APPLICATION FILED TUNE 14, 1902.

3 SHEETS-SHEET 3.

H0 MODEL.

UNITED STATES PATENT OEEICE.

ADOLPH F. RIETZEL, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THOMSON ELECTRICWELDING COMPANY, OF LYNN, MASSACHUSETTS, A CORPORA- TION OF MAINE.

CLAMP DEVICE FOR ELECTRIC WELDING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 719,508, dated February3, 1903.

Atplication tied June 14,1902.

T a/ZZ whom it may concern:

Be it known that I, ADOLPH F. RIETZEL, a citizen of the United States,and a resident of Lynn, in the county of Essex and State ofMassachusetts, have invented a certain new and useful Clamp Device forElectric Welding-Machines, of which the following is a specification.

My invention relates to clamping devices Io designed more particularlyfor use on electric welding or metal-working machines, and is especiallyadapted for clamping fiat stock formed into rings, bands, hooks, &c.,straight pieces, and angle-work.V The devices are also adapted forholding round and square stock to be welded or otherwise Worked whenelectrically heated.

The successful operation of electric welding-machines depends almostWholly upon the zo construction of the clamping devices, which have tobe adapted for various kinds of Work and which must, moreover, becapable of holding the work tightly and be so constructed that the workmay be quickly put in and taken from the clamps. They must also bestrong enough to hold the work iirmly in the jaws without slipping whenthe pressure is applied to complete the weld or perform other operationswhen the metal has been softened 3o by the current to the requireddegree.

The principal object of my invention is to provide a clamping devicethat may be operated with great rapidity and which shall also clamp thework evenly over its entire width,

3 5 which is very essential, especially for welding thin stock.

A further object of my invention is to provide a simple and effectiveconstruction whereby the clamping devices may be adjusted for differentthicknesses of stock and to further overcome any tendency of adistortion or twisting of the clamp-supporting frame or body bytheapplication of pressure to the clamp-jaw for the purpose of setting itdown upon the work.

To these ends my invention consists of the improved constructions andcombinations of levers, cams, and jaws, with means for adjusting them,as hereinafter more particuserinNo. 111.602. (No model.)

larly described, and then specified in the 5o claims.

Myinvention consists also in details of construction, as moreparticularly hereinafter set forth and claimed.

ln the drawings, Figure 1 is a plan of an 55 apparatus constructed inaccordance with my invention. Fig. 2 is a front elevation of theapparatus. Fig. 3 is a side elevation thereof. Fig. 4 is a longitudinalsection through the lever which carries one of the clamping-jaws. 6oFig. 5 is a perspective view showing the form of the clampjaw itself.Fig. 6 is a perspective view ofthe end of the jaw-carrying lever,showing the stud which supports the jaw.

l indicates the terminals of the secondary of an induction-coil whichsupplies heatingcurrents to the apparatus, as usual in the art. Theseterminals are for any source of current, preferably alternating current.Secured to them in any suitable manner are the platens k7o or blocks 2,of some good conducting material, like copper, one of which is supportedupon guides 3 andpis capable of being moved toward the line of weldingor forming by the operation of a lever -t and link 5, connecting thesame with the platen, as usual in the art. Upon the platens 2 aremounted the clamp devices for holding the Work. Each platen is providedwith a set ofclamping devices, and a description of one will sufce forthe 8o other.

6 is a base-plate of the frame or body on which the clamping devices aremounted and which is detachably bolted to the platen 2. From the plateor base 6 rise two posts 7and 85 8, connected, preferably, by the strut9 to strengthen the frame against strain applied in the act of clampingthe upper jaw down upon the work. Upon the post 7 is pivotally mountedthe lever l0, which carries the up- 9o per clamping-jaw ll at itsfarther end. The pivotal end of the lever is mounted on a blockvertically adjustable and guided upon the post 7 by means of a nut l2,engaging with a threaded bolt attached to said block and operating inobvious manner to change the height of the fulcrum or pivotal point ofthe lever above the base 6 of the frame. This adjustment provides forconsiderable variations of thicknesses in the work to be clamped by thejaw 11.

13 is the usualjaw-actuatingleveremployed for forcing thejaw down uponthe work. Said lever is furnished at its lower end with a cam 14 forthis purpose. The pivotal support for the lever 13 is upon avertically-adjustable block or carrier 15, which is suitably guided onthe upper part of the post 8, constituting a part of the frame thatcarries the clamping device. The block or support 15 is made adjustableup and down on the frame, preferably by means of a screw 16, to whichthe block or support 15 bears the relation of a nut. The screw 16, asseen more clearly in Fig. 2, carries a thumb-piece 17 and is suitablymounted in the frame and has a bearing at its lower end, as shown at 18,in said frame. The block 15, guided in an opening in the post 8, asdescribed, is furnished with ears 19, which hold it against lateraldisplacement. The guide-opening is closed at its top bythe detachableplate 20, which permits insertion or removal of the block or carrier 15,and said plate also forms one of the bearings or supports for theadjustable screw 16, as clearly indicated.

To prevent distortion or twisting of the clamp-supporting frame, and tothereby secure the utmost rigidity of the parts, which is necessary foruniform work, I provide the block or carrier 15 with alaterally-extending arm or projection 21, which has a bearing upon anextension 22 of the post 8, rising from base 6. This arm or projection2l obviously will tend by engaging` the post 22 to prevent the inner endor portion of the block 15 from rising under the strain applied by thecam when the lever 13 is thrown to bring the jaw down upon the work. Inother words, it serves to prevent twisting in a vertical plane of theblock or carrier 15 and also obviously takes the strain from the upperportion of the frame which carries the screw 16: The arm 21 engages thepost 22 by an adjustable abutment furnished by screw 23. By this means asolid engagement of said arm with the base or post rising therefrom isfurnished for all adjustments in the height of the block 15, whichcarries the clamping-lever. The adjustment in the height of theclamping-lever by means of the screw 16 affords a fine or delicateadjustment for varying thicknesses of work, while for a coarseradjustment the pivotal end of the lever should be also adjusted by meansof the nut 12. As will be obvious, this double adjustment for largervariations in the size of the work preserves the mechanical relation ofthe parts and gives a practical parallel motion of the lever carryingthe clamping-jaw for all classes or sizes of work.

The retractor-spring which raises the jaw 11 when the cam-leveris turnedto release the work is indicated at 25. This spring is attached at oneend to the lever 10 and at its other end to an arm 26, connected with avertically-adjustable block 15 or some other part moving therewith, sothat changes in the position of the block will not disturb the tensionof the spring. The clamp-jaw 11 is mounted on the inside of the lever 10to bring the line of pressure as near the line of heating as possible.To enable the clamping devices to accommodate themselves readily toslight irregularities in the form of the work, the jaw is properlymounted on the lever so as to be capable of a slight rocking movement.This may be accomplished by the construction shown in detail in Figs. 4,5, and 6.

27 is a stud bolted to the leverand adapted to receive the jaw in suchmanner as to permit it to rock on said stud. 28 represents screws whichhold the jaw on the stud. These screws pass through openings in saidlever, which are slightly larger than the screw itself, to permit alimited rocking movement. On the face of the jaw next the lever is atongue 29, which has a slight taper from the center outward and whichfits a straight opening formed in the face of the lever. This tongueaids in taking the strain off the clamp, and the taper thereof permitsthe slight rocking movement which is desirable for small irregularitiesin the work itself.

The jaw 11 is preferably made of steel, and the other portions of theclamp-supporting frame already described as bolted to the platen 2 arealso made of steel or other magnetic material adapted to choke off theflow of any alternating currents designed for the work. The currents arepassed mainly to the work throughthe lower jaw'O of the clamping device.The jaw 30 is of copper or other good conductor and is in direct unionor contact with the platen 2. It is clamped firmly down against theupper face of said platen' by the base-plate 6, which is formed, asshown more fully in Fig. 3, with an opening tapering inwardly andadapted to lit down upon the swelling base of the jaw 30, so that theaction of the screws 31 or other clamping devices which fasten the clampdown upon the platen will be to firmly secure the lower jaw 30 inelectrical union with the platen also.

As will be seen, jaws 30 of different size or shape may be readilysubstituted for one another in the apparatus by simply detaching theclamp frame or body 6 from the platen.

The device is shown as iemployed in the operation of welding the twopieces 32 to one another, the line of welding and heating beingindicated at 33.

Various changes in the details of construction and form of parts may beresorted to without departing from my invention. Thus, in particular,the means for securing an adjustable abutment between the arm orextension 21 and the base of vthe clamp-body may be varied, particularlyas to the location of the screw.

The manner of supporting the jaw upon the lever hereinbefore describedis particularly advantageous in these respects-to wit,

IOO

IIO

that it gives a large surface of stud which shall be in contact with thejaw, while at the same time it permits the jaw to be readily removed bysimply turning back the screws 28, so as to be disengaged from the jawitself, after which the said jaw may be slipped off the stud.

What I claim as my invention is- 1. In an electric metal-workingapparatus, the combination substantially as described, of a levercarrying a clamp-jaw, a verticallyadjustable support therefor, athreaded bolt connected to said support and an adjustingnut.

2. In an electric metal-working apparatus, the combination substantiallyas described, of a jaw-carrying lever vertically adjustable at itspivoted end, an actuating earn-lever for operating on the jaw-carryinglever to clamp the work, a vertically-adjustable supporting block orcarrier on which the cam-lever is mounted, and an adjusting-screwconnected with said support for adjusting the position of the same asand for the purpose described.

3. In an electric metal-working apparatus, the combination with aclamp-jaw and lever carrying the same, of a cam-lever, a block orsupport constituting a nut and supporting said cam-lever, a clamp-frameand an adjusting-screw mounted in said clamp-frame.

4. In an electric metal-Working apparatus,

the combination substantially as described,

with the actuating-lever for the clamp-jaw,of a vertically-adjustablesupport and an arm extending therefrom 'and provided with an adjustableabutment device, as and for the purpose described.

5. In an electric metal-working apparatus, the combination substantiallyas described with the clamping-jawand actuating-lever, of a support l5in the form of a nut and upon which said lever is pivoted and twoadjustingscrews passing through said nut one adapted to change theposition of the lever with relation to the work and the other to furnishan adjustable abutment adapted to take up the strain applied in clampingwork.

6. In an electric metal-Working apparatus, the combination of ajaw-carrying lever pivoted to one side of the work and adapted to swingin-a line transverse to the line of pressure applied to the work whenheated, and a clamping-jaw pivotally mounted on a stud projectingfrom-the side of said lever nearest the line of heating and adapted toswing in a line parallel to the plane in which the lever swings, as andfor the purpose described.

7. In an electric metal-Working apparatus, the combination substantiallyas described, of a jaw-carrying lever, an actuating cam-lever mountedupon an adjustable support,and a retracting-spring connected at one endto said lever and at the other end to an arm carried by said support.

8. In an electric metal-Working apparatus, the combination substantiallyas described with the frame carryingthe clamping device and detachablysecured to the platen, of a removable clamp-jaw fastened down by saidframe upon the face of the platen, as and for the purpose described.

9. In an electric metal-Working apparatus, the combination substantiallyas described with the jaw-carrying lever, of a jaw mounted on the studof said lever and having a tapered tongue engaging with a slot in thelever, as and for the purpose described.

10. The combination with the jaw-carrying lever, of a stud projectingtherefrom, a jaw mounted to turn on 'said stud and screws adapted tohold the jaw upon the stud and passing through enlarged openings in thele- Ver, as and for the purpose described.

1l. The combination in an electric metalworking apparatus, of aclamping-jaw and support therefor, a stud upon which the jaw is adaptedto turn, a Jtongue or projection by which the lever and jaw areinter-locked but which is adapted as described to permit a limitedrocking movement of the jaw, and means for detachably holding the jawupon the stud.

Signed at Lynn, in the county of Essex and State of Massachusetts, this12th day of June,

ADOLPH F. RIETZEL. Witnesses:

C. I. LINDsEY, GEO. W. N. OHADWELL.

